Direct current visual evoked potentials on light and dark adaptation process.

采用枕部直流电放大技术记录视觉诱发电位(VEP)，观察短期明暗适应过程。刺激模式为持续时间为10、50、100、500、1000ms的明暗阶梯函数和5、10、20赫兹的明暗闪光串。从50个原始数据中计算平均DC VEP和AC VEP(时间常数0.3s)。DC-VEP的适应性漂移对应于光和暗刺激：光适应时上移(负)，暗适应时下移(正)。有适应因子的列车视觉诱发电位模拟比无适应因子的模拟结果更好。提出了一个包含起始、偏移、适应、对比度和延迟因素的视觉诱发电位模型。一些用于实验的计算机程序Easy(脑电分析系统)被介绍给实验心理学的研究人员。

Visual evoked potentials(VEP) were recorded by direct current amplification from Occipital to investigate the short term light and dark adaptation process. Stimulus patterns were light and dark step functions with the duration of 10, 50, 100, 500, 1000ms, and light and dark flash trains with 5, 10 and 20Hz. Averaged DC VEP and AC VEP(time constant 0.3s) were computed from 50 raw data. Adaptational shifts of DC VEP were found corresponding to light and dark stimulations: upward shift(negative) was for light adaptation and downward shift(positive) was for dark adaptation. Simulation of train VEP with adaptation factor was fitted better than without adaptation factor. A VEP model was proposed including onset, offset, adaptation, contrast and delay factors. Some of computer programs for experiment, EASY(EEG Analysis SYstem), were introduced to researchers of experimental psychology.